Therapeutic use of 90Y microspheres.

Glass microspheres 20-30 microns in diameter containing either 31P or 89Y that can be activated by neutron bombardment to 32P or 90Y respectively, have been produced for intra-arterial radiotherapy of liver tumors. The spheres are insoluble in body fluids, non-toxic, and can concentrate in liver tumors of animals by direct injection into the hepatic artery. This gives a higher radiation dose to the tumor than can be achieved with external beam therapy. Trials in rabbits and dogs have proven successful and this product (90Y TheraSpheres) is now entering limited human clinical trials.